This invention as the jet propulsion boating elements is very much related with my first U.S. Pat. No. 4,341,058 xe2x80x9cExercycle Mower Apparatus xe2x80x9d granted on Jul. 27, 1982 and the Second and third U.S. Pat. No. 4,657,514 xe2x80x9cAmphibious Pedal Powered Sailboatxe2x80x9d on Apr. 14, 1987.
That is, in 1982 while developing the gearing system of the Exercycle Mower, it was found the fact that the minimum revolutions of the grass cutting blade required 900 r.p.m. whereas subsequently the gearing mechanism was settled with the design of 1,040 r.p.m. which is equivalent to the small capacity of a outboard Gas engine; and that during the period of developing the invention xe2x80x9cAmphibious Pedal Powered Sail Boatxe2x80x9d, it was found that the stern of the boat hull molded with fiberglass reinforced resin is comprised with the perpendicularly projected screw propeller stand firmly holding with a seal bearing box and upper half round cavity covering screw propeller whereby the round cavity behind the screw propeller significantly affected to enhance efficiency of its thrusting power, while reducing propeller noise as compared with a outboard motor boat. As such that, the present invention of the jet propulsion inboard boat is merited with the intensive research achievements during the development of the previously U.S. patented inventions including the xe2x80x9cPedal Powered Exercycle Mowerxe2x80x9d and the xe2x80x9cPedal Powered Sailboat.
The present invention of inboard boat is provided with the Pressure Chamber in the stern of the hull, and the screw propeller is installed in the forward section of the Pressure Chamber with the propeller shaft that is supported by the Seal Bearing Box firmly fixed at the lower part of the screw propeller stand protruded from the central part of the boat hull whereby to connect the screw propeller shaft with the shaft of the Drive Power Unit. As such that, this invention of the inboard boat is remarkably distinguished from other inboard boat in the following facts: 1) the boat hull has a hollow cavity running from the central part of the hull to the end of the stern, 2) the Pressure Chamber is comprised of the upper part and lower part, and the upper part is processed together with the boat hull and the lower part separately processed is joined with the upper part by bolts and nuts, and 3) the screw propeller is placed at the point right inside of the inlet opening of the Pressure Chamber, whereby the propeller is well protected from possible damage by rocks or other things in the water.
In this context, numerous research was carried out through the web side in domestic and world wide, however, there were no significant answers to the queryxe2x80x94only saying that there is a remarkable improvement in the field of airplane jet propulsion, but no significant development in jet propulsion boating. Although the applicant of the present invention searched through the internet of www.uspto.gov/ with use of paraphrases such as xe2x80x9cJet Propulsion Pedal Boatxe2x80x9d and xe2x80x9cJet Propulsion Motor Boatxe2x80x9d that were responded with xe2x80x9cNo patents have matched with your query.xe2x80x9d
The present invention of the Jet Propulsion boat has a boat bull molded with use of reinforced plastic materials in which the bow section is provided with sailing device, the central section of the hull longitudinally along the keel is hollowed that is gently curved and elevated to have the Drive Power Unit Housing Device precisely balanced in order to link the drive power mechanism shaft with the screw propeller shaft which is supported by the Seal Bearing Box that is firmly based at the lower part of the propeller stand perpendicularly projected downward at the inlet opening of the Pressure Chamber comprising of in two partsxe2x80x94upper part and lower partxe2x80x94the upper part combined with the hull and the lower part detachably fixed to the upper part thus shaping cylinder with the constricted exhaust opening in the stern of the hull where it is facing the rudder the shaft of which is manipulated by means of bevel gears and transmission shaft that is handled by the steering wheel standing on the Drive Power Housing Device. Since the boat hull is formed with the upper part of the pressure chamber, the lower part detachably is joined together with the upper part with bolts and nuts whereby to function not only for pressure chamber but also for protection of the screw propeller with no worry of crushing damage while in operation.
The present invention is designed to operate the inboard boat by means of three drive power sources such as the pedal powered mechanism, D.C. motor and Gas engine, each respectively provided with the hollowed rail tracks on both sides longitudinally at the lower part of a drive power unit thus matched with the protruded rails on the Drive Power Unit Housing Device and tightened to it with use of the Drive Power Unit Holding Bolt. When car topping, the drive power unit can be detached from the boat hull, and at the launching site the drive power unit is combined with the housing device through the sliding means thereon and tightening it with the bolt thereof, and then the boat is launched on the water by means of couple of the transport wheels at the boat end, and while in operation on the water, the jet propulsion system makes less noise and functioning with powerful thrusts that create appropriate reactions to propel the boat. At present it is found that the pedal power mechanism is possible to activate propelling function to the same level of a small D.C. motor and Gas engine capacities, because the D.C. motor can make about 40 lbs./m thrust and Gas engine with about 1,000 r.p.m.